C ++ 11类型推导vs const char * [英] C++11 type deduction vs const char *

问题描述

在 GotW 94 < a>，Herb Sutter在经典C ++声明之间划分区别。

In GotW 94, Herb Sutter draws a distinction between the "classic C++" declaration

const char* s = "Hello";

和现代风格

auto s = "Hello";

他告诉我们， s的类型有一个 / code>，其中 auto 样式更正确。

He tells us that there's a "subtle difference in the type of s, where the auto style is more correct".

但是...有什么区别？我的印象是， const char * 是引用字符串文字的正确方法。此外，当我问我的调试器（lldb），它似乎认为类型实际上是一样的：

But... what's the difference? I was under the impression that a const char * is the correct way to refer to a string literal. Further, when I asked my debugger (lldb), it seems to think the types are actually the same:

* thread #1: tid = 0x1756c2, 0x0000000100000f8f test`main + 31 at test.cc:4, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
    frame #0: 0x0000000100000f8f test`main + 31 at test.cc:4
   1    int main(void) {
   2        const char* s = "Hello";
   3        auto t = "Hello";
-> 4        return 0;
   5    }
(lldb) fr v
(const char *) s = 0x0000000100000f91 "Hello"
(const char *) t = 0x0000000100000f91 "Hello"

Sutter所指的微妙差别在哪里？

Where's the subtle difference Sutter refers to?

推荐答案

你不完全清楚Herb说的是什么（上下文很重要），但无论如何类型是一样的。

You're not entirely clear on what Herb stated (context is important), but anyway the types are the same.

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